Microwave Photonic System for Nonuniform Frequency Diverse Array Radar

A microwave photonic system, which has the ability of providing amplitude, frequency and phase control of a microwave signal, for use in a nonuniform frequency diverse array (FDA) radar is proposed and experimentally demonstrated. Microwave signal amplitude and phase controls are realized by adjusting the bias voltages of a dual-polarization dual-parallel Mach Zehnder modulator. A frequency offset on the microwave signal, which is needed in an FDA radar, is introduced by Serrodyne modulation. A range, angle and time dependent beampattern can be generated by controlling the amplitude, frequency and phase of a microwave signal in each array element of an FDA radar. Experimental results are presented that demonstrate the proposed structure can generate the frequency offsets required for a 32-element nonuniform FDA radar. Using the measured frequency offsets, a dot-shaped beampattern can be produced by a nonuniform FDA radar.